With the development and progress of electronic technology, various human-machine interfaces are widely used in electronic devices. Touch panels are more humanized than other human-machine interfaces and have advantages of intuition and small volume. Therefore, touch panels are more and more popular. Common touch panels currently on the market include resistance type touch panels, capacitance type touch panels, surface acoustic wave type touch panels and infrared type touch panels and so on. The capacitance type touch panels are waterproof, anti-static, anti-glare, anti-scratching, anti-reflective, and fingerprint resistant. Besides, the capacitance type touch panels can achieve multi-touch sensing function. Therefore, the capacitance type touch panels have strong competitiveness. Moreover, the capacitance type touch panels include surface capacitance type touch panels and projected capacitance type touch panels. Compared with the surface capacitance type touch panels, the projected capacitance type touch panels have advantages of high durability and low drift phenomenon. Thus, the projected capacitance type touch panels are regarded as mainstream technology of the capacitance type touch panels in future.
FIG. 1 is a schematic view of a conventional touch panel. FIG. 2 is a schematic view of the touch panel of FIG. 1, showing a finger of a user touching the touch panel. FIG. 3 is a schematic view of a sensing module inside the touch panel of FIG. 1, wherein in order to clearly show relation between sensing electrodes, a part of the sensing electrodes is omitted. Referring to FIGS. 1 to 3, a conventional touch panel 100 includes a surface panel 110, a plurality of sensors 120, a plurality of scan lines S1, a plurality of data transmission lines DL1 and a controller 210. The sensors 120 are disposed on a bottom surface 112 of the surface panel 110, and the sensors 120 include a plurality of sensing electrodes 120s and a plurality of driving electrodes 120d. The controller 210 provides scan signals and the scan signals are transmitted to the driving electrodes 120d by the scan lines S1. The data transmission lines DL1 are configured to transmit sensing signals of the sensing electrodes 120s to the controller 210 for calculating. When the touch panel 100 is touched by a finger of a user, a capacitance between the finger and the sensing electrodes 120s is increased. Therefore, a touch position can be obtained according to variation of electrostatic capacitance of the sensing electrodes 120s. 
However, in the touch panel 100, since a driving end is in series with the sensing electrodes 120s of a sensing end, signals output from some of the sensing electrodes 120s located at an end far away from the driving end are greatly decayed because of loading effect. Therefore, the sensing electrodes 120s in current design are unable to be miniaturized. If the sensing electrodes 120s are too small, variation of electrostatic capacitance of the sensing electrodes 120s is also small. As a result, strength of touch signals is insufficient, and thereby a touch action cannot be distinguished.